To electrically connect two circuit boards to each other, an arrangement may be used in which a first connector is fastened to a first circuit board and a second connector is fastened to a second circuit board, and the first and second connectors are mated to electrically connect the first and second circuit boards. In this arrangement, however, there may be instances when the first and second connectors are fixed at a predetermined position on the first and second circuit boards, and therefore the first and second connectors do not precisely align during mating. As a result, when the first and second connectors are mated, unless one of the connectors is flexible, mating of the first and second connectors is difficult and at least one of the first and/or second connectors or contacts contained therein are susceptible to damage or permanent deformity. Damage to the first and/or second connectors and/or the contacts can result in a deficient electrical connection.
One way to solve this problem is to design either the first of second connector as a floating connector. A floating connector has a mating section formed so that the mating section is capable of moving elastically in at least a horizontal direction relative to a surface of the circuit board to which the floating connector is fixed. The floating connector thereby absorbs strain during mating.
FIGS. 7(A)–7(B) and 8(A)–8(C) show one example of a floating connector 101 (Japanese Utility Model Application Kokai No. S64-16084). As shown in FIGS. 7(A)–7(B), the floating connector 101 is fastened to a first printed circuit board PCB. The floating connector 101 is mated and connected with a mating connector 131. The mating connector 131 is fastened to a second printed circuit board PCB2 that is disposed perpendicular to the first circuit board PCB1. The mating connector 131 includes a housing 140 that extends in a direction of length (i.e., a direction perpendicular to a plane of the page in FIG. 7A or a left-right direction in FIG. 7B). A plurality of pin contacts 150 are attached in two rows in the direction of length of the housing 140. Each of the pin contacts 150 includes a board connection member that is connected by soldering to the second printed circuit board PCB2 and a pin contact member that extends vertically downward from the board connection part.
The floating connector 101 includes a housing 110 that extends in a direction of length (i.e., a direction perpendicular to a plane of the page in FIG. 7A or a left-right direction in FIG. 7B). A plurality of contacts 120 are attached in two rows in the direction of length of the housing 110. Each of the contacts 120 has a fastening member 121 fastened to the housing 110, a soldering tine member 123 connected to the first printed circuit board PCB1, and a pair of contact pieces 124 that contact the corresponding pin contact 150. The contacts 120 are formed by stamping and forming metal plates.
As best shown in FIGS. 8A–8C, the fastening member 121 is formed substantially in a box shape and has a pair of side walls 121a that are separated from each other by a specified interval in the direction of length of the housing 110. A front end wall 121b extends in the direction of length from the front end portion (lower end portion in FIG. 8C) of one side wall 121a to substantially a central portion between the pair of side walls 121a. A rear end wall 121c connects rear end portions of the pair of side walls 121a. A connecting member 122 extends rearward toward a center of the fastening member 121 perpendicular to the direction of length. The connecting member 122 is formed by being bent on an end of the front end wall 121b of the fastening member 121. A soldering tine member 123 extends downward from a rear end portion of the connecting member 122. The pair of contact pieces 124 extends upward from the respective side walls 121a of the fastening member 121. Contact projecting members 125 are formed on facing surfaces of end sections of the contact pieces 124.
The floating connector 101 is mounted on the first circuit board PCB1 by soldering the soldering tine members 123 of the contacts 120 to the first circuit board PCB1, as shown in FIGS. 7A–7B. When the mating connector 131 is mated with the floating connector 101, the pin contacts 150 contact the contact projecting members 125 of the contacts 120, so that an electrical connection is established between the floating connector 101 and the mating connector 131. As a result of the soldering tine members 123 extending downward from the connecting members 122, the floating connector 101 can move elastically in at least a horizontal direction (the direction of length of the housing 110 and the direction perpendicular to the direction of length) with respect to a surface of the first printed circuit board PCB1 such that strain created when mating the floating connector 101 with the mating connector 131 is absorbed.
The following problems have been encountered with the floating connector 101 shown in FIGS. 7A–7B and 8A–8C. Since the contacts 120 are formed by complicated forming following the stamping of metal plates, production of the contacts 120 is complicated and time consuming. Further, since the fastening members 121 of the contacts 120 are formed substantially with a box shape, the dimensions of the contacts 120 are relatively large in the direction of length of the housing 110 and the direction perpendicular to the direction of length, so that it is difficult to use the floating connector 101 in compact high-density electronic devices. Additionally, when the contacts 120 are fastened to the housing 110, the contacts 120 are not attached to the housing 110 all at one time, instead each of the contacts 120 is attached individually after being cut from a contact carrier. Accordingly, assembly of the floating connector 101 is time consuming.
Another example of a floating connector 201 is shown in FIG. 9 (Japanese Patent Application Kokai No. H4-370677). The floating connector 201 is devised such that strain created at the time of mating the floating connector 201 with a mating connector (not shown) is absorbed. As shown in FIG. 9, the floating connector 201 is fastened to a surface of a first printed circuit board (not shown) and is mated and connected with a mating connector (not shown) fastened to a second printed circuit board (not shown). The floating connector 201 includes a substantially frame-form first housing 210 that extends in a direction of length. A second housing 220 is inserted into an opening 211 in the first housing 210 so that a gap is left therebetween. A plurality of contacts 230 disposed in a single row in the direction of length is attached to the second housing 220. Each of the contacts 230 includes a fastening member 231 fastened to the second housing 220, a strain absorbing member 232, a board connection member 233 connected to the first printed circuit board (not shown), and a pair of contact members 234 that contact a mating contact (not shown).
The contacts 230 are formed in a substantially flat plate shape. The fastening member 231 is formed into a substantially rectangular shape formed exclusively by the stamping of a metal plate. The strain absorbing member 232 is formed into an elastic shape and extends from a lower end of the fastening member 231 via a plurality of curvilinear members. The strain absorbing member 232 is formed exclusively by stamping of the metal plate. The board connection member 233 is formed so that it extends downward from an end portion of the strain absorbing member 232 and is formed by stamping and forming of a metal plate. The pair of contact members 234 extends upward from the fastening member 231. Contact projecting members 235 are formed on facing surfaces of end sections of the contact members 234.
The floating connector 201 is mounted on the first printed circuit board (not shown) by connecting the board connection members 233 of the contacts 230 to the first circuit board (not shown) by soldering. When the mating connector (not shown) is mated with the floating connector 201, the mating contacts (not shown) contact the contact projecting members 235 of the contacts 230, so that an electrical connection is established between the floating connector 201 and the mating connector (not shown). In this state, the second housing 220 of the floating connector 201 is constructed so that the second housing 220 can move elastically in at least a horizontal direction (the direction of length of the second housing 220 and the direction perpendicular to the direction of length) as a result of the board connecting members 233 extending downward from the strain absorbing members 232 that are formed in an elastic shape with the plurality of curvilinear members. The strain that is generated when mating the floating connector 201 with the mating connector (not shown) is thereby absorbed.
The following problems have been encountered with the floating connector 201 shown in FIG. 9. Since the contacts 230 are formed exclusively by the stamping of metal plates, except for the base connection members 233, the contacts 230 can be made in an easy and timely manner. When the contacts 230 are fastened to the second housing 220, however, the contacts 230 can not be fastened all at one time. Because the planes of the strain absorbing members 232 and the base connection members 233 attached to the contact carrier in the state in which the metal plates have been stamped differ from the row disposition direction of the contacts 230 (a direction in which the contacts 230 are lined up in row form in the second housing 220, i.e., the direction of length of the second housing 220), each of the contacts 230 must be individually attached after being cut from a contact carrier. Accordingly, assembly of the floating connector 201 is time consuming. Additionally, although the contacts 230 are formed in a substantially flat plate shape such that the dimensions of each of the contacts 230 in the attachment pitch direction, i.e., the direction of length of the second housing 220, is small, the strain absorbing members 233 of each of the contacts 230 extends via a plurality of curvilinear members such that the contact 230 has a relatively large dimension in the direction perpendicular to the direction of length. Accordingly, it is difficult to use the floating connector 201 in compact high-density electronic devices.